Focal Plane Shutter

The 35mm Single Lens Reflex (SLR) camera is fundamentally a 45° hinged mirror set behind a lens which reflects the image up to a focusing screen on the camera top. As the shutter release is pressed the mirror flips up to: i) Form a seal under the focusing screen to prevent light from entering the camera through the viewing lens. ii) Move out of the way of the lens and film. When the mirror reaches the horizontal position it fires a focal plane shutter just in front of the film to make an exposure. Distances are arranged so that the Read more